Just starting out. How important is identification?

I’m looking to get into fishing specifically as a food source. I’m a rather anxious person and I know I’ll always be second guessing my own identification of what fish I’ve caught. How important exactly is the identification of fish? Are there certain fish I just can’t eat that I should know how to identify? Or are most freshwater fish edible? I live and will be fishing in the American south if that helps.